JP2003522467A - Apparatus and method for scheduling packet data service in wireless communication system - Google Patents

Abstract

(57) [Summary] In a mobile communication system, a method is provided for allocating packet data to be transmitted to a wireless packet data channel of a base station in response to a packet traffic transmission request to a plurality of terminals. The method comprises the steps of combining a packet traffic transmission request of a wireless packet data channel to a terminal, selecting at least one of the terminals from the combined packet traffic transmission request, and transmitting a data rate and a data rate to the selected terminal. Transmitting a channel allocation message including information on a transmission section and a start time of the data transmission section to each selected terminal, and transmitting packet data to the selected terminal at a data transmission rate at a start time of the data transmission section; And a process.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an apparatus and method for allocating a traffic channel in a wireless communication system, and more particularly to an apparatus and method for allocating a packet traffic channel.

[0002]

[Prior art]

FIG. 1 shows a structure of a conventional wireless communication network, and FIG. 2 shows a method of allocating a wireless traffic channel in the conventional wireless communication network of FIG.

A method for assigning a wireless traffic channel to a terminal in a conventional wireless communication network will be described with reference to FIGS. 1 and 2.

When assigning a wireless packet data channel to a terminal, a base station controller (Base St
ation controller: hereinafter referred to as BSC) 111-11M determines whether or not a wireless packet data channel can be assigned to the terminal.
(Base Transceiver System: hereinafter referred to as BTS). Upon receiving the wireless packet data channel allocation request in step 211, the BTS receives the wireless packet data channel (e.g., an additional channel (supplemental channel: SCH in the CDMA-2000 system) in step 213) in step 213. Check if it can be used. In this case, the BTS also checks if there is power available or if there is a code available in the CDMA system. If the wireless packet data channel can be assigned, then the B
The TS sends a channel assignment message to the BSC by performing steps 215 to 219, reverses the position of the resource with respect to the radio packet data channel assigned to the terminal, and uses the resource by another terminal. After that, signaling messages related to wireless packet data channel assignment are transmitted to and received from the terminal. If there is no available wireless packet data channel, the BTS sends a reject message in step 221 to the BS.
Reach to C and request allocation of said wireless packet data channel after a predetermined time.

However, the above-described wireless traffic channel allocation method has the following problems. In the following description, it is assumed that the "radio traffic channel" or "radio packet traffic channel" is the same as the supplemental channel (SCH) for transmitting radio packet data.

First, the channel allocation when there is an available wireless packet data channel will be described. From a predetermined time before the base station transmits / receives data to / from the terminal, other users are allocated wireless packet data. No data channel available. That is, the wireless packet data channel is assigned to the corresponding user in advance from the time when the BTS assigns the channel, and the assigned channel is wasted until the traffic is actually transmitted and received. become. This significantly reduces the performance of the wireless packet data channel. For example, 30 to allocate the wireless packet data channel.
Assuming that a time of 0 ms is required and that traffic exchange between the terminal and the base station actually takes about 300 ms, the total time for which the wireless packet data channel is allocated to the corresponding terminal is 600 ms. become. However,
Since the traffic is actually exchanged for 300 ms, the remaining 300
The ms becomes unavailable to other terminals and the allocated channels are wasted. As a result, the use efficiency of the wireless traffic channel decreases.

Next, since the wireless packet data channel is assigned to a specific user in a line-type manner, the user does not transmit or receive packet data through the wireless packet data channel unless the user releases the channel. However, other users cannot use the resource. Therefore, there is a problem of a decrease in channel efficiency and fairness among users. In addition, even if the user does not transmit or receive packet data through the wireless packet data channel, the user has to pay for the total time allocated to the wireless packet data channel. You will have to pay a higher fee for the amount of packet data sent and received over the packet data channel.

[0008]

[Problems to be Solved by the Invention]

Accordingly, it is an object of the present invention to provide a scheduling apparatus and method for reserving allocation of wireless traffic traffic channels for servicing packet data in a wireless communication system.

Another object of the present invention is to provide an apparatus and method for allocating wireless packet traffic channels in a wireless communication system.

Still another object of the present invention is to allocate a channel to a plurality of users by introducing a packet switching method, and immediately after the user uses the allocated channel, the allocated channel is allocated. An object of the present invention is to provide a device and a method for canceling.

Another object of the present invention is to select a leg of a packet data channel when a base station of a wireless communication system has a plurality of legs.
An apparatus and method are provided.

Another object of the present invention is to provide an apparatus and method for obtaining radio information for scheduling by collecting radio information for allocating a packet data channel in a base station of a radio communication system. .

Yet another object of the present invention is to provide an apparatus and method for solving the problem of frame offset collision of packet data channels in a base station of a wireless communication system.

Yet another object of the present invention is to provide an apparatus and method for resolving erroneous recognition of a packet data channel assigned to a terminal in a base station of a wireless communication system.

[0015]

[Means for Solving the Problems]

The present invention for solving the above object provides a method of allocating packet data to be transmitted to a wireless packet data channel of a base station in response to a packet traffic transmission request to a plurality of terminals in a mobile communication system. The method includes a step of combining the packet traffic transmission requests of the wireless packet data channel to the terminal, a step of selecting at least one of the terminals from the combined packet traffic transmission requests, and the selected terminal. A data transmission rate, a data transmission period, and a channel allocation message including information about a start time of the data transmission period to each selected terminal, and the packet data at the start time of the data transmission period. Transmitting to the selected terminal at a data transmission rate.

[0016]

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may obscure the subject matter of the present invention.

In the following description, SCH is used for wireless packet traffic channel to allocate packet data channel and packet traffic channel,
It is assumed that the scheduling _period R _{SCHEDULING_INTERVAL} is set to 260 ms, the data transmission period R _DURATION is set to 80 ms, and when scheduling the wireless packet channel, 3 out of 5 candidate terminals are selected. However, it will be apparent that various modifications can be made by those skilled in the art without departing from the scope of the invention.

Before describing the embodiments of the present invention, first, a method for scheduling and allocating packet data channels in a wireless communication system according to the present invention will be summarized.

Embodiments of the present invention introduce a reservation (or scheduling) scheme for allocation of wireless packet data channels. Therefore, even if a wireless packet data channel is assigned to a specific terminal, another user may use the wireless packet data channel before the specific terminal can actually transmit and receive traffic through the assigned wireless packet channel. Channels can be used. Therefore, the wireless packet data channel continuously operates in pipe lining by a plurality of users. In the above method,
In the wireless communication system, by allocating the packet data channels by a scheduling method, it is possible to maximize the efficiency of the wireless channels for the service of the packet data.

In addition, in the embodiment of the present invention, by introducing the packet switching concept into the wireless communication system, a wireless packet data channel is quickly allocated to the terminal, and the wireless packet data channel is allocated during the allocated time. After using the wireless packet data channel, the channel is released immediately. Therefore, in the wireless communication system, it is possible to prevent a small number of users from monopolizing the wireless packet data channel having limited high-class resources.

Further, in the embodiment of the present invention, when a plurality of legs exist in the base station, a leg selection method for allocating a radio packet data channel is proposed, so that efficient channel allocation performance is achieved even during handoff. I will provide a. In addition, the embodiment of the present invention proposes a method in which the base station collects radio information for allocation of the radio packet data channel in order to collect information for scheduling the packet data channel. Further, the base station proposes a method for efficiently performing power control of the wireless packet data channel in order to enable efficient power control in an environment such as CDMA-2000, which is an international standard. . In addition, according to an exemplary embodiment of the present invention, in order to solve a problem that occurs when a frame offset of a CDMA scheme operates in a scheduling algorithm, a method for the base station to solve a problem of frame offset collision of the wireless packet data channel is provided. provide. Further, the embodiment of the present invention prevents the malfunction of the terminal by proposing a method for the base station to solve the problem of erroneous recognition of a radio packet data channel assignment message generated in the terminal.

[0022]   Hereinafter, the embodiment of the present invention as described above will be described in detail.

The radio traffic channel allocation and scheduling method proposed by the present invention is based on a CDMA system and can be applied to all high-speed transmission environments. Therefore, the embodiments of the present invention can be applied to CDMA-2000 systems, UMTS systems, and wideband CDMA systems that are based on CDMA systems and provide high-speed wireless data transmission services.

In the description of the present invention, a wireless communication network based on the CDMA-2000 system will be mainly described.

The method of allocating and scheduling the wireless traffic channel proposed in the embodiment of the present invention is performed in the wireless communication network shown in FIG. As shown in FIG. 3, the wireless communication network to which the present invention is applied includes the following elements.

Here, a terminal (Mobile Station: MS) means a communication device carried by a wireless communication subscriber. The terminal is a device based on the CDMA system, and can support voice and data and composite support of voice and data. Base Station System:
BSS) is a device that directly communicates with the terminal in a wireless communication network. The base station manages radio resources, controls mobility of terminals, and interfaces with a wired communication network.

In particular, the base station is a base transceiver system (BTS) 1
01 to 10N and a base station controller (Base Station Controller: BSC) 111 to 11M. The BTSs 101 to 10N mainly manage the radio resources through a direct interface with the terminal, and the BSCs 111 to 11M control the corresponding BTSs 101 to 10N. Here, the BSC and the BTS may be combined into one device. However,
In general, a plurality of BTSs are concatenated and connected to one BSC.
The embodiment of the present invention is applied to the latter, and one BSC shown in FIG.
It has a tree structure, a star structure, or a ring structure in which 101 to 10N are connected.

A mobile switching center (MSC) 120 supports a gateway function for a wired voice switching network such as PSTN (Public Switched Telephone Network) in the case of voice service, and in the case of line type data service. , Interworking function (IWF) to support interworking with a packet data network through a device 150. In the following description, it is assumed that the wired voice switching network 160 is PSTN. Further, the MSC 120 is
LR (Home Location Register) 121 and VLR (Visitor Location Register)
It supports mobility management of the terminal through interfacing with 123.

The HLR 121 is a device that stores the home position of the terminal. HL
The R121 stores main subscription information such as location related information and quality of service information for the subscriber.

The VLR 123 performs location management in the area of the current terminal to track the location of the terminal when the current location of the terminal is not the home location.

A PDSN (Packet Data Serving Node) 130 links the wired packet data service network 140 with the BSCs 111 to 11M. The data communicated through the PDSN 130 is the packet data and is connected to the wired packet data service network 140.

The embodiment of the present invention is applied to the terminal and the base station among the components of the wireless communication network as shown in FIG. In the following description, the "base station BSS" is defined as a term including the base station controller BSC and the base station transceiver BTS. Furthermore, it is assumed that the wireless communication network is based on the CDMA-2000 system. Also, the wireless communication network will be described with reference to a current mobile communication network including MSC, HLR, VLR, and PDSN. However, the present invention includes other elements similar to the MSC, HLR, VLR, and PDSN. It can also be applied to other mobile communication structures including.

Next, in the description of the operation according to the embodiment of the present invention, the description will be given with reference to the wireless channel configuration of the CDMA-2000 wireless communication network.

In order to support the wireless data service, the terminal and the base station require a path capable of exchanging signal information with each other, and the path is called a channel.
In the CDMA-2000 system, a channel for exchanging the signal information is a fundamental channel (FCH) and a dedicated control channel (Dedica).
Ted Control Channel (DCCH), and the terminal and the base station can exchange signaling messages using these channels. Where the FC
H is used for transmitting a voice signal, and the DCCH is used for transmitting control information. Also, both the FCH and the DCCH can perform a function of exchanging dedicated control information with a terminal in communication. The FCH and the DCCH can also transmit and receive traffic for packet data services, but in the case of these channels, a very small amount of packet data is transmitted and received through a low speed route. In addition, the packet data service using the FCH and the DCCH does not require separate channel allocation and scheduling. Therefore, the operation of transmitting and receiving the packet data through the FCH and the DCCH will be omitted from the following description.

However, unlike the FCH and the DCCH, transmission / reception of high-speed packet data between the terminal and the base station is performed through another dedicated channel. For example, the CDMA-2000 system includes an additional channel (Supplemental Channel: SCH) for exclusively communicating data, and a high-speed wireless packet data transmission / reception function between the base station and the terminal using the SCH. To help. The relationship between the SCH and the FCH / DCCH is as follows. The FC
The H and the DCCH are maintained even when there is no data transmission / reception between the terminal and the base station, and these channels are mainly used for transmitting / receiving signaling messages. Therefore, as the amount of packet data traffic sent and received increases,
The base station allocates the SCH for communicating the packet data at high speed by transmitting and receiving the signaling message with the terminal through the FCH or the DCCH. When the SCH is assigned, the high speed packet traffic is transmitted and received between the terminal and the base station through the SCH. Then, when there is no traffic to be transmitted or received, the base station and the terminal are
The signaling messages for releasing the assigned channel are exchanged through the FCH and the DCCH, and then the assigned SCH is released.
Here, the allocated SCH channel may be released without transmitting / receiving the signaling message for releasing the allocated channel between the base station and the terminal.

Therefore, it is assumed that the high speed wireless traffic channel used in the method of scheduling, allocating and releasing the packet traffic channel according to the embodiment of the present invention is mapped to the SCH channel of the CDMA-2000 system, A signaling message transmission / reception path (or channel) between the terminal and the base station for allocation of a high speed wireless traffic channel is defined as the FCH or the DCCH.

[0037]   Hereinafter, embodiments of the present invention will be specifically described.

In the high-speed wireless communication network, the CDMA-2000 base station according to the embodiment of the present invention schedules a wireless traffic channel according to a packet switching method and allocates the packet traffic channel according to the scheduling result.

Generally, there are two methods for assigning a wireless traffic channel: a line type method and a packet switching method. The circuit-based method is, regardless of whether or not the terminal actually transmits and receives the traffic through the allocated channel after allocating a wireless traffic channel to a specific terminal, such as allocation of a traffic channel for a voice service. , A structure in which the radio traffic channel assigned by another user cannot be used. The packet switching method has a structure in which only the subscribers who actually need to transmit and receive the packet request the allocation of the wireless traffic channel, and the allocation time of the wireless traffic channel is also limited. Therefore, when allocating the channel in the packet switching method, the "pipe" is allocated to all users for a predetermined time, and when the time is over, it is allocated to other users. Hereinafter, in the description, the “pipe” has the same meaning as the “channel”. Generally, the circuit-type scheme is applied to a service in which traffic continuously arrives, such as a voice service. However, the packet switching method, like the Internet service,
Due to the burst nature of the traffic, it applies to services that arrive intermittently. The line-type scheme may be supported by the same scheme as that used for voice channel allocation.

Therefore, in the embodiment of the present invention, it is assumed that the SCH process according to the line-type scheme is performed as follows. Here, a description will be given of a method of allocating and scheduling a wireless traffic channel of the packet switching system, and a description of a method of operating a wireless packet data channel of the circuit type system will be omitted. Further, it is assumed that the scheduling method described in the embodiment of the present invention is performed for the remaining band after supporting the voice call and the line data call.

In the embodiment of the present invention, some terms are defined as follows for allocation and scheduling of the wireless traffic channel.

First, the “radio traffic channel allocation time” is the SC for the CDMA-2000 system because the radio traffic channel is the SCH.
It is defined as H set time (SCH Setup Time: SS_Time). The wireless traffic channel allocation time, after the scheduler of the wireless traffic channel determines allocation of the wireless traffic channel (SCH), the base station and the terminal, the preparation for transmission and reception of the wireless traffic channel, This is the time required to actually transmit and receive the traffic by starting the wireless traffic channel processing. The shorter the wireless traffic channel allocation time,
The wireless traffic channel can be assigned quickly.

Variable data rate, Discontinuous transmission of the SCH
ransmission (DTX) and a method using a scrambling code (Scrambling Code), when it is not necessary to continuously transmit and receive a signaling message for assigning the wireless traffic channel between the terminal and the base station. The radio traffic channel allocation time can be set to 0 ms.

The second, “radio traffic channel scheduling _period” means R _{SCHEDULING_INTERVAL} which is a scheduler operation parameter described below. The wireless traffic channel scheduling period indicates a period in which the wireless traffic channel scheduler is activated and operates periodically. The shorter the wireless traffic channel allocation and scheduling section, the more the system load increases. However, the packet data traffic can be efficiently transmitted and the wireless channel can be quickly responded to.

Third, the “transmission unit time of the wireless traffic channel” is the minimum time unit required when the wireless traffic channel is allocated, and is N times the minimum time unit (where N = 1, 2, 3). , 4, ...) are defined as the data transmission section R _DURATION . In the following description, since the frame period of data transmitted through the SCH channel in the CDMA-2000 system is 20 ms, it is assumed that the transmission unit time of the wireless traffic channel is 20 ms. In the embodiment of the present invention, R _DURATION is referred to as a “data transmission section” for transmitting the packet data through the wireless packet data channel. As the unit time for transmitting the data through the wireless traffic channel becomes shorter, the wireless traffic channel is allocated and deallocated more frequently, so that the wireless link is exchanged between the terminal and the base station. The amount of channel allocation related messages increases.

Embodiments of the present invention handle allocation and scheduling of forward radio traffic channels transmitted from the base station to the terminal. In this connection
Generally, the wireless data service has asymmetric characteristics. That is, although the amount of the packet traffic transmitted from the terminal to the base station on the reverse link is small, on the contrary, the packet traffic on the forward link transmitted from the base station to the terminal is transmitted. Is large. Therefore, it is necessary to improve the efficiency of the forward radio traffic channel in order to maximize the efficiency of the radio resources. Therefore, in the embodiment of the present invention, only the operation of the forward radio traffic channel is considered, and it is assumed that a low transmission rate channel is allocated for the reverse radio traffic channel. Further, the reverse radio traffic channel
(Reverse Supplemental Channel: R-SCH) allocation is assumed to follow the procedure of CAC (Call Admission Control) of the FCH and the DCCH.

Embodiments of the present invention can provide simple or complex structures by adjusting operational parameters. For example, in order to support the simple structure, the method according to the embodiment of the present invention may set the following operating parameters. In other words, the single radio traffic channel structure is
-Pipe) structure (that is, a structure for operating one or a small number of SCH channels to transmit the packet data at high speed) and transmitting data to the subscriber through the wireless traffic channel R _DURATION By assigning the same to each other, development and experiment become easy.

When implementing the embodiments of the present invention, some parameters may need to be adjusted. That is, when the embodiment of the present invention is applied to the CDMA-2000 system, the following restrictions may occur, and these restrictions are applied according to the technology to be applied, and are not included in the content of the present invention. It has no effect.

First, when trying to maximize the quality of the voice service, during the CAC process,
The power allocated for the data service by the voice band allocation value α is
The power that can be used for channel allocation for the data service and remains in the voice service band during SCH scheduling cannot be used for SCH allocation. That is, in the embodiment of the present invention, it is assumed that the remaining power other than the power set for the voice service is used for the SCH allocation. However, in order to improve the processing rate of the data service, the power not used in the voice service band (i.e., of the power set for the voice service, the power currently used for the voice service is used. Not reserve power) can also be used.

Second, the base station BSS performs scheduling for allocating the SCH to the terminal in units of the set scheduling _period R _{SCHEDULI NG_INTERVAL} . In the embodiment of the present invention, the scheduling interval R _{SCHEDULI NG_INTERVAL} is assumed to be _{260 ms} . However, the scheduling period of the SCH can be set to be 260 ms or more or less.

Third, the base station BSS collects radio information for the SCH scheduling in a 260 ms period.

Fourth, if the frame offset of the SCH is the same as the frame offset of the FCH / DCCH, a frame offset collision may occur between subscribers to which the SCH is assigned within the same scheduling period. is there. To prevent this, the frame offset of the SCH is allocated separately from the FCH / DCCH, or if the frame offset of the SCH does not exist, a guard interval for distributing collision points is allocated.

Fifth, the base station BSS includes the base station controller BSC and the base station transceiver B.
When divided into TS, the BSC is a predetermined amount of RLP (Radio Link Protocol).
) Flow control with the BTS such that packets are present in the BTS.
trol) can be supported.

Sixth, the BTS supports RLP packet buffering, sequence management, and a reservation function of RLP packet transmission at the time of DTX, and “last transmitted RLP packet to the BSC through an inband path”. The sequence "of.

In the seventh embodiment of the present invention, the SCH data transmission _period R _DURATION is 80.
Assume ms. However, the data transmission section of the SCH is 80 m.
It is also possible to set it above or below s.

Eighth, ESCAM (Extended Supplemental Cha) for SCH allocation
The Nnel Assignment Message can omit the ACK / NACK process.

Ninth, if the FCH / DCCH supports soft handoff and the number of legs for the terminal is two or more, the leg selection algorithm is performed. Selecting one of the two or more legs by performing the leg selection algorithm. Here, the leg is one of the base station transceivers BTS.

[0058]   Furthermore, in the present invention, the following operational parameters are defined.

“Scheduling _period R _{SCHEDULING_INTERVAL} ” indicates a time period during which the radio traffic channel scheduler is periodically activated for the assignment and scheduling of the radio traffic channel.

The value of the scheduling interval R _{SCHEDULING_INTERVAL} is equal to that of the base station BSS.
Is set to be larger than a time value required when allocating the wireless traffic channel to the terminal, or should be set to the same (R _{SCHEDULING_INTERV AL} ? (The base station _{allocates the} wireless traffic channel to the terminal. Time required for allocation)).

[0061] The "data transmission section R _DURATION", the radio traffic channel scheduler is a section for assigning the radio traffic channel to the terminal, the data transmission section of the radio traffic channel during the corresponding terminal of the R _DURATION In the section that can be exclusively communicated with the base station through the wireless packet data channel (
Or time). In the embodiment of the present invention, as described above, it is assumed that the data transmission period is 80 ms. Also, in the embodiment of the present invention, the R _{DU RATION} is set to be the same for all terminals. However, the R _{DURATI ON} can be variably set according to the class of the terminal.

“Β” is a time value required to sort the frame offset of the radio traffic channel when the frame offset exists in the CDMA-2000 system, and is defined as 20 ms. The value β is set to 0 if the frame offset of the radio traffic channel is 0 ms.

[Table 1] shows recommended parameter values for the SCH scheduling method of the CDMA-2000 system according to the embodiment of the present invention.

[Table 1]

To explain the packet channel allocation and scheduling technique, it is considered in the embodiment of the present invention that the base station BSS is divided into the BSC and the BTS. In addition, the embodiment of the present invention will be described with reference to an environment in which the BSC and the BTS are logically implemented by a plurality of processors.
This is to explain the present invention more clearly. However, in an actual implementation, the plurality of processors can be designed as one processor, and the BSC and the BTS can also be designed as a single base station device. In particular, the embodiments of the present invention will be described only with respect to the processor required when supporting the wireless packet data service.

[0065]   First, the configuration of the BSCs 111 to 11M in FIG. 3 will be described.

The MMCP (Main Media Control Processor) is a media control processor (Media Control Processor) that supports a function of controlling a path for actually transmitting and receiving packet data and an error control function. In the CDMA-2000 system, the MMCP is an RLP (Radio Link Protocol), a MAC (Medium Acces
s Control) and interfacing with a wired internet network.
The MMCP uses a flow control function to transfer packet data transmitted to each user to an RMCP (Radio Media Control Processor).

The MCCP (Main Call Control Processor) is a call control processor (Call Control Processor) that provides a main function of processing a signal message between the terminal and the base station and a transmission / reception function of a wireless traffic channel assignment message. is there. In addition, the MCCP is a pilot strength (pilot stren) received from the terminal.
It supports a function of collecting information about gth) and a function of transmitting the collected pilot strength to the MMCP.

[0068]   Next, the configuration of the BTSs 101 to 10N in FIG. 3 will be described.

RRMP (Radio Resource Management Processor) is the RMCP of the BSC.
Considering the radio channel information together with buffer information assists the function of allocating the radio traffic channel to a specific user. The RRMP is
It is a processor that performs a scheduling function to actually allocate the wireless traffic channel. That is, the RRMP has the SCH scheduler function according to the embodiment of the present invention.

A RIMP (Radio Information Measurement Processor) performs a function of collecting the radio channel information and transmitting the collected radio channel information to the BSC and the RRMP.

The RMCP buffers the packet data of each user received from the MMCP through the flow control function, and provides the RRMP with information regarding the amount of buffered user packets. Requests SCH radio traffic channel allocation. When the radio traffic channel is assigned by the RRMP, the RMCP sends the received packet to the radio traffic channel during the assigned time.

In the embodiment of the present invention, the operation of scheduling and allocating the wireless packet traffic channel will be described with reference to a CDMA-2000 communication system.

FIG. 4 illustrates a method of packet traffic channel allocation and scheduling according to an embodiment of the present invention in the wireless communication network of FIG.

FIG. 4 shows a scheduling operation when the high-speed wireless packet traffic channel is the SCH in the CDMA-2000 system. The operation according to the exemplary embodiment of the present invention will be sequentially described with reference to FIG. Here, the RRMP is
A function of a collector that collects SCH use request signals for scheduling and allocation of the radio traffic channel, a function of a scheduler that schedules the use of the SCH, and a message generator that generates a scheduling message using the scheduled result. With the function of.

[0075]   In FIG. 4, section t₀-T₁, T₁-T₂, T₂-T₃, T₃-T_Four, T_Four-T_Five, ...
Is the scheduling interval R_{SCHEDULING_INTERVAL}In the embodiment of the present invention,
Are 260 ms each. In step 410, the RRMP collector is
Interval t₀-T₁The SCH usage request is summarized in. Section t₁-T₂In the above
The scheduler schedules the terminal so that t₂In the section after
The SCH is driven for channel allocation so that it can be used (step 420),
The message generator is a channel assignment message for the terminal (here
Then, it is ESCAM). Here summarized by the collector
The generated SCH use request signal is generated by the RMCP of the base station. That is, the book
Scheduling of the SCH according to an embodiment of the invention is performed on the forward link SCH.
Applied to. Therefore, the SCH use request signal is a packet for the forward link.
This occurs when it is necessary to send the remote data. Therefore, the SCH use request signal
Indicates that the base station transmits packet data to a specific terminal through the forward link SCH.
Generated by the base station. In addition, channel allocation
When simultaneously transmitting the channel assignment message to the terminal, the packet data
The message becomes bursty according to the message. Therefore, the above
The channel assignment message should be distributed as shown in step 430 of FIG.
Is desirable. Here, the channel allocation message is the start time of the SCH.
, The transmission rate of the SCH channel, and the data transmission section R_DURATIONincluding. It
From step 440, the terminal determines that the interval t₂-T₃At the set start time
The set data transmission section R at the set transmission rate_DURATIONBetween the S
The wireless packet data is communicated through the CH. Interval t of the SCH channel ₂ -T₃Then, the base station BSS indicates, as indicated by reference numeral 450, the wireless traffic.
Data transmission section R_DURATIONThen, the package for the supported terminal
Data transmission. That is, the base station BSS uses one scheduling
In the interval, a plurality of terminals (three terminals in FIG.
The packet data can be transmitted sequentially to the end). Then the terminal
Receives the packet data at the start of the allocated data transmission section.
The SCH is turned on for communication, and the S signal is transmitted at the end of the data transmission period.
Turn off CH automatically.

In summary, as shown in FIG. 4, in the first scheduling interval t ₀ -t ₁ , the SC
The H usage request signals are compiled (step 410). In the second scheduling period t ₁ -t ₂ , the scheduler of the base station is driven to allocate the SCH according to the scheduling of the terminal according to the combined SCH use request (step 420). The SCH is allocated such that the UE has different SCH start times in one scheduling period (step 430). Then, the channel allocation message including information about a transmission rate and a transmission period used at the set start time is generated, and the generated channel allocation message is transmitted to corresponding terminals at a distributed start time. . Then, in the third scheduling interval t ₂ -t _3, the base station sequentially transmits the radio packet data through the SCH at the start, which is the set to the terminal by the channel assignment message (step 440).

The operations of SCH scheduling and allocation described above are continuously performed. That is, when the SCH is used as in FIG. 4, the collector collects SCH packet traffic transmission requests including terminals a, c, and d in the interval t ₀ -t ₁ .

In the interval t ₁ -t ₂ , the scheduler a selects a terminal a that intends to use the SCH.
, C, and d are scheduled, the message generator generates and transmits the SCH allocation message according to the scheduled result. At this time, the collector assembles SCH packet traffic transmission requests including terminals b, g, and w.

During the period t ₂ -t ₃ , the RMCP sends the radio packet data to the terminals a, c, and d to which the SCH is assigned through the SCH during the set data transmission period R _DURATION. To transmit. Also, the scheduler uses terminals b, g,
And w, the message generator generates and transmits the SCH allocation message according to the scheduled result. At this time, the collector collects SCH packet traffic transmission requests including terminals a, c, and h.

As described above, in each scheduling period, the SCH use request,
It can be seen that the allocation of the SCH channel and the transmission of the wireless packet data over the allocated SCH are performed simultaneously. The above operation is continuously performed. Also, as can be seen from the above description, the allocation and de-allocation of the SCH are performed in the scheduling period. Therefore, the SC
Since the H channel is allocated and released quickly, the use efficiency of the SCH can be maximized.

[0081]   Hereinafter, the above operation will be described in detail.

First, in step 410 of FIG. 4, if packet data to be transmitted to the terminal exists in the base station, the RMCP generates the SCH use request signal and the RR.
The MP collector collects the SCH usage request information.

To explain the operation of step 410 more specifically, the traffic received from the wired packet data network is buffered by the BSC's MMCP,
The MMCP conveys to the BTS information about the arrival of the packet and the amount of traffic received. In this case, the information transmitted to the BTS may include only buffer size information of the MMCP, or the actual RLP packet may be transmitted to the BT through a flare control function between the RMCP and the MMCP.
S RMCP. In the embodiment of the present invention, the case of transmitting the actual traffic to the RMCP will be mainly described. The RMCP is
Information on the data amount of the RMCP buffer is transmitted to the RRMP of the BTS. As a method for informing the RRMP of the buffer size, the RMCP periodically provides the MS information of the entire RMCP, or transmits the buffer size information of each MS, and the RRMP transmits the information. There is a way to collect.

Second, in step 420 of FIG. 4, the scheduler is activated to allocate SCHs to a plurality of terminals that intend to use the SCH in the next scheduling period.

The operation of step 420 will be described in more detail. The RRMP SCH channel allocation algorithm is activated every scheduling interval R _{SCHEDULING_INTERVAL} . A PFQ (Pseudo Fair Queuing) algorithm can be applied to apply intelligent QoS (Quality of Service) in the RRMP. The RRMP determines the SCH according to the SCH channel allocation algorithm.
Information about the code number, the start time, and the data transmission _period R _{DU RATION} of the wireless traffic channel is assigned to the corresponding MS. The RRMP provides the SCH assignment message to the MCCP according to the assigned information.
The RRMP provides the SCH allocation message to the RMCP for buffering and start time processing.

Third, in step 430 of FIG. 4, the SCH channel allocation message allocated in step 420 is distributed and transmitted to the terminal.

To explain the operation of step 430 in more detail, the MCCP sends and receives signaling messages to and from the terminal according to the received SCH allocation message.
The time when the BSS starts exchanging signaling messages for SCH allocation is distributed according to the start time allocated to each terminal through the scheduling interval R _{SCHEDULING_INTERVAL} .

Fourth, in operation 440 of FIG. 4, each terminal communicates RLP packet data with the base station through the SCH channel during the set transmission period at the set start time.

To explain the operation of step 440 more specifically, the MMCP transmits the RLP packet to the RMCP through flow control according to the transmission rate and the data transmission duration of the wireless traffic channel, and transmits the RMCP. Transmits the traffic at the set transmission rate during the data transmission period R _{DURATI ON} of the wireless traffic channel at the allocated start time.

In step 450 of FIG. 5 and FIG. 4, the RLP packet data is actually transmitted through the SCH channel between the BS and the MS in a scheduling period.

To explain the operation of step 450 in more detail, a transmission start time and a transmission rate of the wireless packet allocated by the RRMP may be different for each subscriber. At step 450, it is assumed that the number of SCH channels is one. However, the number of SCH channels can be more than one. The SC
The transmission start time of the wireless packet traffic transmitted through the H channel is
It may be different for each subscriber within the next scheduling interval R _{SCHEDULING_INTERVAL} . In step 450, the packet traffic data transmission sections R _{DURA TION} is assumed to be fixed for example to a specific value of 80 ms. However, the data transmission period R _DURATION can be variably set by the subscriber.

That is, in the wireless packet data channel communication device of the base station of the mobile communication system according to the embodiment of the present invention, the RRMP schedules the use of the SCH, the function of a collector that collects the packet traffic transmission requests of the SCH. It performs the function of a scheduler and the function of a message generator that generates a message according to the scheduled result. First, the operation of the collector will be described. The RMCP receives the SCH packet traffic transmission request of the radio packet data channel transmitted from the terminal and receives the RRM.
To P. The RRMP collector then aggregates the packet traffic transmission requests for the channel from the RMCP. Second, explaining the operation of the scheduler, the RRMP schedules the radio packet data channel by selecting at least one terminal from the terminals that have requested to use the radio packet data channel, and then the RRMP The selected terminal determines a transmission rate, a data transmission period in which the wireless packet data channel can be used, and a start time of the data transmission period. Third, explaining the operation of the message generator, the RRMP sends the determined SCH allocation information to the RM.
To the CP, the RMCP sends the channel assignment message to the BSC's MMCP via an in-band path, and the MMCP sends the received channel assignment message to the MCCP. Then, the MC
The CP generates the radio packet data channel assignment message including the SCH assignment information.

Then, the channel transmitter of the physical layer of the BTS transmits the radio packet data channel assignment message to the terminal. Then, the channel transmitter transmits data through the radio packet data channel during the determined transmission period at the scheduled start time and releases the SCH channel with the terminal at the transmission end time.

FIG. 5 shows a traffic channel allocation algorithm according to an embodiment of the present invention. The RRMP performs the radio traffic channel allocation and scheduling operation in the scheduling _period R _{SCHEDULING_INTERVAL} .

Referring to FIG. 5, in step 511, the RRMP of the BTS periodically collects the packet traffic transmission requests of the SCH from the terminal to create a program for allocating and scheduling the wireless traffic channel. To drive. In the CDMA-2000 system, since the wireless traffic channel is mapped to the SCH channel, a module that performs allocation and scheduling of the wireless traffic channel is called an SCH scheduler.
In step 513, the SCH scheduler selects a terminal that can use the SCH channel from terminals that have requested to use the SCH channel. In the embodiment of the present invention, it is assumed that the SCH scheduler first selects five terminals from the terminals requesting the use of the SCH channel, and selects three terminals from the selected five terminals. Therefore, in the embodiment of the present invention, it is assumed that three terminals can use the SCH in one scheduling period. In step 513, as a method of selecting five candidate terminals, an intelligent Qos support bill such as a PFQ (Pseudo Fair Queuing) algorithm can be applied, and as a result, the SCH
Select subscribers to be candidates for allocation. Here, the QoS parameters include subscriber class, message class, and data size. Then step 51
At 5, the SCH scheduler finally selects a terminal having no frame offset collision in an environment where the SCH uses a frame offset based on the five terminals. In the embodiment of the present invention, a case will be described in which the number of terminals finally selected is three. Then, in step 517, the scheduler determines, for each of the selected subscribers, the transmission rate of the SCH channel, the SCH.
The start time of the channel and the end time of the SCH channel (the end time of the data transmission period) are calculated.

In steps 519 and 521, the SCH scheduler requests the MCCP to send and receive the SCH assignment message with the terminal after updating the scheduler database using the finally calculated information. At this time, B
The MCCP of the SC disperses and transmits the SCH allocation message based on the SCH allocation start time point for each terminal. By doing so, it is possible to suppress an increase in noise that occurs when the SCH assignment message is simultaneously transmitted on the radio channel. Also, by transmitting the SCH allocation message in a distributed manner, it is possible to solve the problem that the SCH allocation message allocated to the terminal in the previous scheduling period and the current SCH allocation message cannot be distinguished. That is, in the CDMA-2000 mobile communication system to which the present invention is applied, before the SCH allocation message is received in the previous scheduling period and data is transmitted / received through the allocated SCH, the new SCH allocation message is When received in the scheduling interval, the terminal will confuse the two SCH allocation messages. In this case, the terminal ignores the previously received SCH assignment message. Therefore, when the SCH allocation message is distributed and transmitted as described above, the terminal may transmit the previously allocated SCH.
Since the next SCH allocation message is received at the time of transmitting the message through (or after that), the above confusion problem can be solved.

Then, in steps 523 and 525, the base station waits until the SCH allocation message transmission time is reached. Here, when the SCH allocation message time is reached, the base station transmits the SCH allocation message in step 527. Also, in step 529, if there is any SCH assignment message waiting for the SCH assignment message transmission time to arrive, the process returns to step 523. Meanwhile, in steps 527 to 529, when the start time included in the arrived SCH allocation message arrives, data transmission is performed at the set transmission rate during the transmission period. According to an embodiment of the present invention,
The above operation is repeated three times.

The method proposed in the present invention is based on the SC in the current CDMA-2000 standard.
Limitation due to the frame offset of H may occur. A method for solving this problem is shown in FIG. As indicated by reference numeral 640, “[1]” indicates a time determined by the scheduler, “[2]” indicates a time when the SCH is assigned to the terminal, and “[3]” indicates “[4]” indicates a time when the terminal prepares for SCH processing, and “[4]” indicates a time when the SCH is released at the start time.

[0099]   Referring to FIG. 6, as indicated by reference numeral 610, the SCH message is
It is distributed and exchanged at the start of each transmission section. As indicated by reference numeral 620,
The user can use the frame offset and the previous scheduling interval information to
Selected. That is, the frame offset of the SCH is the FCH / DCCH
The current scheduling interval if it is assigned the same as the frame offset
R_{SCHEDULING_INTERVAL}Is assigned to the PFQ (Pseudo Fair Qu
euing) algorithm, selected by users according to the following criteria:
Be done. First, the five SCHs assigned by the PFQ algorithm
Of candidate subscribers, the scheduler is selected as a result of the PFQ.
From among the subscribers that have no frame offset collision, three subscribers are selected. This
, The last RLP frame data transmission period R of the previous scheduling period _DURATION Is assigned to the current scheduling interval R_{SCHEDULING _INTERVAL} When the candidate is selected by the PFQ in
The subscriber shall have the radio traffic according to the scheduling set time (SS_Time).
Channel data transmission section R_DURATIONCurrent schedule to avoid conflicts between
Ring section R_{SCHEDULING_INTERVAL}Last data transmission section R_DURATIONDivided into
Applied. If the frame offset collision still occurs, try another subscription.
To the last data transmission section.

That is, in the data transmission period (the data transmission period of the G and H users) before the A user transmits the packet data through the assigned SCH in the period T ₁ -T ₂ of FIG. wherein the SCH in an interval T ₂ -T ₃ of used by a user
Schedule assignment messages not to be transmitted. Here, before the packet data of A user is transmitted in the interval T ₁ -T _2, if the SCH assignment message of A user to be assigned in the interval T ₂ -T ₃ is transmitted, the interval T ₁ data a user between -T ₂ and T ₂ -T ₃ is likely to come to mutual interference. In addition, as shown by reference numeral 630, when the number of terminals that are going to use the SCH is only one (A user in the section T ₃ -T ₄ in FIG. 6), it is 3 As in the second sch allocation procedure, the RRMP scheduler
All the data transmission sections R _{DU RATION} (sections T ₄ -T _{5 in} FIG. 6) of the radio traffic channel in the scheduling section can be assigned to a single terminal.

FIG. 7 illustrates a call processing process for allocating and scheduling wireless packet traffic channels in a CDMA-2000 system according to an embodiment of the present invention. In a basic environment, the RRMP scheduler transmits the RLP packet to the RMCP, and the RMCP receives the RLP received from the BSC.
Buffer the packet and transmit the SCH allocation request to the RRMP. In FIG. 7, BTS-A is the selected BTS (selected BTS), and
B is the old BTS (Old BTS).

Referring to FIG. 7, the BSC's MCCP determines in step 701 that the corresponding terminal (MS).
The pilot strength information of the above is transmitted to the MMCP. In this connection, the terminal PSMM (Pilot strength Measurement Message) / PSMMM
When the report interval (report interval or transmission interval) of (Pilot strength Measurement Mini Message) and the report interval of PMRM (Power Measurement Report Message) are the same, the quality of the reverse link deteriorates. Therefore, in this case, it is desirable to make the transmission time asynchronous with the terminal at the frame level.

In steps 702 and 703, the RTS of the BTS-A transfers information about power available for the SCH to the RRMP and RMCP. The RIM
Transmitting the usable power information from P to the RRMP is for determining the transmission rate of the SCH, and transmitting the usable power information from the RIMP to the RMCP is for selecting a leg. Is. Then, the R
The MCP transfers the usable power information received from the RIMP and the last transmitted RLP sequence to the MMCP through the in-band path in step 704. Here, the reason that the RMCP transmits the sequence number of the last transmitted RLP to the terminal is to support the DTX function. That is, in the embodiment of the present invention, the BTS controls the transmission of the RLP frame according to the environment of the channel link. In particular, the BTS controls transmission of the buffered RLP frame according to the channel environment after buffering internal RLP frame information. Therefore, the BTS is
It does not send an RLP retransmission request to the BSC, but instead just sends the last number of the currently transmitted RLP frame to the BSC. The BSC is the BT
Since the size of the RLP frame transmitted from S is known, the RLP frame transmission state of the BTS can be confirmed by the RLP frame number reported from the BTS.

Upon receiving the usable power information and the last transmitted RLP sequence number from the RMCP, the MMCP, in step 705, transmits the pilot strength information of the corresponding terminal received in step 701 to the in-band. RM through the route
Communicate to CP. Then, the RMCP conveys the pilot strength information of the terminal received from the MMCP to the RRMP in step 706.

In steps 712 to 716, the BTS-B performs step 7 according to BTS-A.
The power available for the SCH and the last transmitted RLP frame number are transmitted to the BSC through the same process as that performed in steps 02 to 706. Here, the BTS-A and the BTS-B are legs for a specific terminal.

As described above, if there are two legs for a particular UE, the MMCP performs a leg selection algorithm in step 750. The leg selection algorithm will be described in detail with reference to FIG. If the leg is changed by the leg selection algorithm, the MMCP may change the RMCP-B (
Alternatively, a Handoff Indication message is transmitted to the Old RMCP through the in-band path. When the RMCP-B receives the handoff instruction message, the RMCP-B flushes the buffer after transmitting the RLP packet up to the assigned data transmission period when allocation of the SCH to the terminal is not completed. ) Do. The sequence of packets finally transmitted by the RMCP-B is delivered to the MMCP in the same manner as performed in step 704.

In step 758, the MMCP transmits the RLP frame to the RMCP-A of the BTS that allocates the SCH to the corresponding MS. The transmission of the RLP frame is performed by a flow control algorithm between the MMCP and the RMCP-A, and the transmission amount is determined such that the buffer capacity of the RMCP-A for the terminal maintains a specific range. Then, the RMCP-A becomes 759.
In step, the SC including RLP Q-Size information of the terminal periodically or individually
The H allocation request message is transmitted to the RRMP.

In step 760, the RRMP-A performs SCH scheduling in the same method as that of FIG. The RRMP-A sends the SCH for the UE according to the scheduling result determined by the scheduler in step 770.
The allocation information is transmitted to the RMCP-A. Then, the RMCP-A transfers the SCH allocation information to the MMCP through the in-band route according to the scheduling result determined by the scheduler in step 771. In response to the SCH assignment message, the MMCP sends step 7
At 72, the SCH allocation command is transmitted to the MCCP. Then, the MC
In step 773, the CP transmits and receives an SCH allocation message to and from the terminal. In this case, the L2 (Layer-2) retransmission function is not applied to ESCAM. Upon receiving the ESCAM transmitted from the MCCP, the terminal may additionally transmit an acknowledgment signal ACK for the ESCAM in step 774.

Then, the RMCP-A transmits the RLP packet to the terminal during the data transmission period at the start time in step 775, and in the DTX mode, the RMCP.
-A postpones the transmission of the RLP packet. Also, the RMCP-A transmits the sequence number of the last transmitted RLP frame to the MMCP through an in-band path as in step 704. Further, the RLP retransmission due to the occurrence of the error of the RLP frame is performed by the MMCP of the BSC and the RLP of the terminal.
Carried out between.

In the leg selection process of step 750, if there are two or more legs for the MS, the MMCP drives the leg selection algorithm to select a leg for the MS. Also, as shown in FIG. 5, the SCH scheduling process of step 760 is performed, and in this process, the RRMP processes the RM.
Based on the RLP buffer size reported from the CP, PFQ (Pseudo Fair
Queuing) algorithm selects a terminal to which the SCH is assigned, and calculates a start time of the assigned SCH and an end time of a data transmission duration of the wireless traffic channel.

In an embodiment of the present invention, the leg selection algorithm is provided in consideration of a case where the terminal performs a handoff through FCH and DCCH. In this case, the terminal is in a state of communicating with two BTSs (that is, a handoff state in which the two BTSs are connected to one terminal through the FCH and / or DCCH).
Therefore, the two legs are linked to the BSC for the old BTS (OLD BTS) and the new BTS (NEW BTS). Since the SCH has a fat pipe structure using one or a few channels, the FCH or the DCC is used.
Uses much higher transmit power than H. Therefore, the SCH generates a lot of noise when it is connected to two or more legs in a handoff state. Therefore,
The SCH is preferably connected to one leg even in the handoff state.

First, as a unit of information collection time, the PMRM reporting period is 180 at the minimum and 2
60 ms, 280 ms, 340 ms, 360 ms, 420 ms, 440 ms, and 480 ms (5 * 2 ⁿ + 4 * k frames) can be used for the PMRM reporting period. The PSMM and the PSMMM are not periodic. Periodic PSMM
In the case of an order (Periodic PSMM order), the minimum section is 800 ms. Furthermore, if the PSMM transmission period of the terminal is the same as the PMRM transmission period,
The quality of the reverse link is degraded. Therefore, it is desirable to transmit data asynchronously at the frame level between the terminals.

[0113]   The operating position of the leg selection algorithm is defined by the MMCP.

Regarding the operation period of the leg selection algorithm, the leg selection frames for each user do not coincide with each other (Frame Asynchronous). In an embodiment of the present invention, the PMRM interval for the data call is set to 260 ms. Also, the leg selection result is the RRMP through the RMCP.
Provided to.

In this case, the information necessary for the leg selection from the BTS has two types for each leg as shown in FIG. The first information is, as shown in FIG. 7, that each of the BTSs transmits the power available for the SCH to the BSC. Here, since there is no direct route from the RRMP to the MMCP, the BTS transmits the usable power information to the BSC through an in-traffic path from the RMCP to the MMCP. The second information is pilot strength information. In the case of the pilot strength information, the MCCP is the PMRM.
, PSMM, or the latest value obtained by processing PSMMM is used.

FIG. 8 shows an algorithm for selecting a leg in the BSC using the above information.

Referring to FIG. 8, in step 811, a dedicated channel for transmitting control information (
In the CDMA system, soft handoff of FCH / DCCH (hereinafter referred to as FDCH) is started (FDCH Soft Handoff Start). In step 813, it is checked whether the FDCH soft handoff is finished. If the FDCH soft handoff is finished, the BSC sends the handed off FDCH in step 831.
Select a leg.

On the other hand, if the soft handoff of the FDCH is not completed in step 813, the BSC selects PMRM, PSMM as pilot strength information in step 815.
, Or PSMMM is received. Then, in step 817, the BSC searches for a leg that maximizes a rate indicator. Here, the searched leg may be a new leg (old leg) or a new leg (currently connected).
It can also be a new leg). After searching the leg, the BSC checks in step 819 whether the searched leg is an old leg. If the sought leg is the old leg, this means that the current leg is in better condition than the new leg. Therefore, the BSC selects the searched leg as an old leg in step 821.

However, in step 819, the searched leg is replaced with the old leg.
If not, the BSC determines in step 825 whether the rate indicator of the new leg is greater than the sum of the rate indicator of the old leg and the hysteresis value (LEG_Sel_Hysteresis) set for leg selection. To inspect. That is, in an embodiment of the present invention, when the rate indicator of the new leg is larger than the leg indicator of the old leg and satisfies the set hysteresis value, the new leg is moved to the previous leg. (o
ld leg). Therefore, in step 825, if the above condition is not satisfied, the BSC proceeds to step 821 to select the previous old leg, and if the above condition is satisfied, proceeds to step 827. And select the new leg.

After selecting the leg in step 821 or step 827, the BSC determines the selected leg as the old leg in step 823 and returns to step 813. By performing the above, the BSC selects a BTS having a higher transmission rate from the two or more BTSs connected to the terminal in the soft handoff state.

[0121]   Hereinafter, the leg selection algorithm will be described in more detail.

When driving the leg selection algorithm to select a leg, the MMCP of the base station controller BSC receives the pilot strength from the MCCP and determines the R of each BTS.
The power value available for the SCH is received from the IMP. The MMCP first calculates a transmission rate that can be served by each leg for the terminal, and then supports a maximum transmission rate of the calculated transmission rates for two or more legs.
Select S.

In an embodiment of the invention, the available speed of each leg (available SCH power (LEG))
After calculating, the first embodiment selects the leg with the highest available speed (Rate_achiev), and after calculating the available rate indicator (Rate_indicator) for each leg, selects the leg with the highest rate indicator value. The second embodiment will be described separately.

First, after calculating the Rate_achiev of each leg, the highest Ra
A first embodiment for selecting a leg having te_achiev will be described.

Assuming that all available SCH power is used by the user, the Rate_achiev of each leg for the user is calculated as follows: Here, since the BSC uses one static value for the pilot power, the pilot power (LEG) is equal to the M.
Suppose it is known to the MCP.

The Rate_achiev of each leg is calculated using the available SCH power of the leg, the pilot power, the pilot Ec / Io provided from the terminal, and the Eb / Nt value required to maintain the performance as follows. Is determined as. Rate_achiev (LEG) = f (Available SCH Power (LEG) / Pilot Power (LEG), Pilo
t rx Ec / Io (LEG), Req Eb / Nt table)

First, using the available SCH power and the pilot power, an SCH offset that is a ratio of the available SCH power to the pilot power is calculated. SCH offset = (Available SCH Power) / (Pilot Power)

In this case, the maximum processing gain (pg) allocated for the available SCH power is calculated as follows. pg = Req Eb / Nt / (Pilot Ec / Io * SCH_offset) where Req Eb / Nt is a received Eb / Nt value at the terminal, which is a value known in advance through simulation, and Pilot Ec / Io is , P
It is a pilot reception Ec / Io value provided from the terminal through a signaling message such as MRM or PSMM.

Finally, since the processing gain at the speed of 9.6 Kbps is 128, the available speed is determined as follows. Rate_achiev = 128 / pg * 9.6kbps

When there are a plurality of legs, the BSC selects the BTS that supports the highest available speed among the calculated Rate_achiev for each leg, and transmits data in the selected legs. Carry out.

When the reverse FCH is assigned, the reverse SER (Symbol Error Ratio) is greater than or equal to the set critical value SER_BAD_THRESH, or when the reverse DCCH is assigned, the reverse pilot Ec If / Nt is less than or equal to the set critical value RPICH_BAD_THRESH, the packet is not scheduled until the selected leg is scheduled in RRMP.

Next, each of the available rate indicators Rate_indicato
A second embodiment will be described in which, after calculating r, the leg having the largest Rate_indicator is selected. In the second embodiment, the rate indicator Rate_indicator can be calculated as follows. Rate_indicator (leg) = Pilot_Strength_dB (leg) + Available_SCH_Power_dB (le
g)

Using the Rate_indicator, the leg selection algorithm according to the second embodiment of the present invention is obtained as follows.

In this case, using the pilot Ec / Io provided from the terminal and the available SCH power, after calculating the Rate_indicator of each leg, the leg having the maximum rate indicator value is selected. for (each leg in the Active Set) Rate_indicator (leg) = Pilot_Strength_dB (leg) + Available_SCH_Power_dB (le
g); Leg = argmaxleg (Rate_indicator (leg));

That is, a leg having a large received pilot power and a large available SCH power at the terminal is selected for the data service.

On the other hand, in order to prevent the ping-pong current situation of the leg in the handoff area, if the rate indicator value of the newly determined leg is smaller than the rate indicator value of the previous leg plus a hysteresis value, the existing leg is not used. Continuously carry out data services. if (Leg == Old_Leg) {Selected_Leg = Old_Leg;} else if (New Leg! = Old_Leg) {if (Rate_indicator (Leg)> Rate_indicator (Old_Leg) + Leg_Sel_Hysteresis) Selected_Leg = Leg; else Selected_Leg = Old_Leg;

The leg selection method according to the second embodiment of the present invention is performed in the process of FIG. 8, and the Rate_indicator is the Rate_achie of the first embodiment.
Used in place of v. Here, the Rate_indicator is the pilot strength (dB) + available SCH power (dB), and the base station controller BSC is in the handoff state and the Rate_indicator of the base station transceiver BTS.
After calculating, select the BTS with the highest Rate_indicator value. In the process of selecting a leg, the process of selecting a new leg is Rate_indic
It is executed when the condition of ator (Leg)> Rate_indicator (Old_Leg) + Leg_Sel_Hysteresis is satisfied.

Also, when the reverse FCH is allocated, the reverse SER is greater than or equal to a set critical value SER_BAD_THRESH, or the reverse DC is
If the reverse pilot Ec / Nt is less than or equal to a set critical value RPICH_BAD_THRESH when a CH is assigned, the packet is not scheduled until the selected leg is scheduled in the RRMP.

On the other hand, in the detailed description of the present invention, the specific embodiments have been described, but it goes without saying that various modifications can be made within the scope of the present invention. Therefore,
The scope of the present invention should not be limited by the above embodiments, but should be defined by the claims and their equivalents.

[0140]

【The invention's effect】

The SCH scheduling and allocation method according to the embodiment of the present invention includes:
It has the following advantages.

(1) By assigning the SCH according to the embodiment of the present invention, it is possible to efficiently support the limited radio resource. (2) The embodiment of the present invention is
The radio channel can be assigned to the terminal according to a scheduling concept. Therefore, the efficiency of using the wireless channel can be maximized by minimizing the section where the wireless channel resource does not exist. (3) Embodiments of the present invention can officially provide services to multiple users through a scheduling concept. (4) The embodiment of the present invention can support the quality of service desired by the system operator by applying the PFQ (Pseudo Fair Queuing) algorithm as requested by the system operator. .

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a conventional wireless communication network.

FIG. 2 is a flowchart showing a method of assigning a wireless traffic channel in a conventional wireless communication system.

FIG. 3 is a diagram showing a structure of a wireless communication network according to an embodiment of the present invention.

FIG. 4 is a diagram showing a method of assigning a wireless traffic channel in a wireless communication system according to an embodiment of the present invention.

FIG. 5 is a flowchart illustrating a process of assigning a wireless traffic channel in a wireless communication system according to an exemplary embodiment of the present invention.

FIG. 6 is a diagram showing an example of allocating a wireless traffic channel under the worst condition in a wireless communication system.

FIG. 7 is a diagram showing a procedure of exchanging a signaling message for assigning a wireless traffic channel in the wireless communication network according to the embodiment of the present invention.

FIG. 8 is a flowchart showing a procedure for selecting a leg during wireless packet data communication in the wireless communication network according to the embodiment of the present invention.

9 is a block diagram showing in detail the configuration of the BTS shown in FIG.

[Explanation of symbols]

101 to 10N base station transceiver 111 to 11M base station controller 120 Mobile Exchanger 121 HLR 123 VLR 130 PDSN 140 Wired packet data service network 150 Interworking function device 160 Wired voice switching network

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE, TR), AE, A G, AL, AM, AT, AU, AZ, BA, BB, BG , BR, BY, BZ, CA, CH, CN, CR, CU, CZ, DE, DK, DM, DZ, EE, ES, FI, G B, GD, GE, GH, GM, HR, HU, ID, IL , IN, IS, JP, KE, KG, KP, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, M G, MK, MN, MW, MX, MZ, NO, NZ, PL , PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, UG, U Z, VN, YU, ZA, ZW (72) Inventor Sung Ju Maen             Republic of Korea, Kyong Gide, 463-070, Song             Nam-shi Yatap-Don Pundang             (No address) Mehma Maul # 201-1001 (72) Inventor Woo Jun Kim             Republic of Korea, Kyonggied 138-130, Song             Parg Ogun-Don (No address) Hu             Daya Apt # 28-1403 (72) Inventor Hong-Song Chan             Republic of Korea, Gyeonggi, 463-050, Song             Nam-si Pundang-gu Seohyun-dong             (No house number) Hyochacheon Denu A             Petty # 703-619 (72) Inventor Hung Chan             Korea, Seoul, 135-284, Gangnam-             Gu Da Chi Dong (No Address) Donger A             RP # # -1110 F-term (reference) 5K030 GA08 HA08 HC01 HC09 HD05                       JL01 JT09 LC09                 5K033 CC01 DA06 DA17                 5K067 AA11 BB21 DD34 EE02 EE10                       EE16 EE72 HH21 JJ12

Claims (13)

[Claims] 1. A method for allocating packet data to be transmitted to a wireless packet data channel of a base station in response to a packet traffic transmission request to a plurality of terminals in a mobile communication system, comprising: A step of collecting the packet traffic transmission requests, a step of selecting at least one of the terminals from the combined packet traffic transmission requests, a data transmission rate, a data transmission section, and the data for the selected terminal Transmitting a channel allocation message including information on a start time of a transmission section to each selected terminal, and transmitting the packet data to the selected terminal at the data transmission rate at the start time of the data transmission section. The process and How to butterflies. 2. The method as claimed in claim 1, wherein the step of selecting a terminal to use the wireless packet data channel comprises a step of selecting a candidate terminal by a PFQ (Pseudo Fair Queuing) algorithm. 3. The step of selecting a terminal that intends to use the wireless packet data channel includes a step of preferentially selecting a terminal that has used the wireless packet data channel in a previous state among the candidate terminals. The method according to claim 2, characterized in that 4. The step of selecting a terminal to use the wireless packet data channel includes a step of preferentially selecting a terminal having a different frame offset from the candidate terminals. Item 2. The method according to Item 2. 5. The step of transmitting a channel assignment message to a terminal that intends to use the wireless packet data channel includes a step of transmitting the channel assignment message in a distributed manner based on a start time of the data transmission period. The method according to claim 1, wherein: 6. The method of claim 1, wherein the wireless packet data channel is an additional channel. 7. A method of scheduling and allocating a radio packet data channel in a base station of a mobile communication system, comprising a step of collecting packet traffic transmission requests of the radio packet data channel transmitted from a terminal in a first scheduling section, In the second scheduling section, by scheduling the packet traffic transmission request, at least one terminal that intends to use the wireless packet data channel is selected, and the transmission rate and the data transmission section used by the selected terminal are selected. , And a start time, and generating a channel assignment message of the wireless packet data channel including information on the determined data transmission rate, data transmission period, and start time, and a third schedule In the session section, the packet data of the corresponding terminal is transmitted at the start time of the data transmission section corresponding to each terminal to which the wireless packet data channel is sequentially allocated, and the data transmission section of the terminal that is finally allocated is transmitted. The step of terminating the transmission of the wireless packet data at the end point of and transmitting the packet data to the last terminal. 8. The method of claim 7, wherein the scheduling interval includes at least two data transmission intervals. 9. The method according to claim 8, wherein the data transmission period is N (N = 1, 2, 3, ...) Multiple of a frame size of the wireless packet data channel. 10. The method of claim 9, wherein the wireless packet data channel comprises a 20 ms frame. 11. The scheduling period may include at least two data transmission periods and a guard interval for preventing a frame offset collision of a terminal to which the wireless packet data channel is assigned. The method described. 12. The step of transmitting the channel assignment message to a terminal that intends to use the wireless packet data channel comprises the step of transmitting the channel assignment message in a distributed manner based on a start time of the data transmission period. The method of claim 7, comprising: 13. A device for allocating packet data to be transmitted to a wireless packet data channel of a base station in response to a packet traffic transmission request to a plurality of terminals in a mobile communication system, the wireless packet data channel for the terminal. A collector that aggregates the packet traffic transmission requests, a selector that selects at least one of the terminals from the aggregated packet traffic transmission requests, a data transmission rate for the selected terminal, a data transmission section, and A message generator that generates a channel allocation message including information about a start time of a data transmission section and transmits the message to the selected terminal; and the packet data at the data transmission rate at the start time of the data transmission section. Selected terminal Apparatus characterized by being composed of a transmission apparatus for transmitting.